9mm guys, will you switch in a post-ban era?
No. Why? (Spare me the caliber, "power" & "stopping power" diatribes.
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I favored my smaller capacity compact & subcompact pistols (6, 7, 8, 9 & 10-rd capacities) even during the last fed ban, and after CA enacted their own state law regarding high capacity feeding devices ... even with the peace officer's exemption in place.
I carried my 7, 8 & 10-rd 9mm's more often than my .40's & .45's back then. Nowadays I find myself carrying my 7 & 9-rd .40's a bit more often, but my 10-rd .45 not very often.
They all see range use for training, practice & quals, of course (as I still keep my hand in things as a firearms instructor & armorer) ... but the larger .45's don't see nearly as much carry usage as my 9's & .40's, due to them not being quite as slim or as small, overall, as the 9's & .40's. (My several 5-shot J's and my LCP see more carry time than my .45's, too.)
Don't get me wrong, as I carried higher capacity issued pistols over the years, on & off-duty. It's just that toward the end of my career I found myself carrying first an issued 8-rd full-size .45, and then either a compact 9-rd .40 or a 7-rd compact .45, and not feeling particularly under-equipped.
If I'd been given my druthers, however, I'd have been satisfied to have carried a previously issued 12-rd 9mm (6906), or even a 8-rd 9mm (3913).
So ... no, I don't envision "switching". No reason to do so.
Naturally, if I couldn't shoot the smaller pistols as well (or better) than the larger ones, I'd probably have chosen the larger ones and dealt with the size & weight issues. The magazines would have been what they were.